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<H1>break</H1>
A new invocation of a top level loop is called as a subgoal
<DL>
</DL>
<H2>Description</H2>

    Used to start a new invocation of the top level loop.  Compiled
    procedures and event handler redefinitions remain valid within the new
    invocation level.  Exiting with a Control-D (or end_of_file) or
    calling exit_block(end) will return the control to the previous level.
    
<H3>Fail Conditions</H3>
   None.


<H3>Resatisfiable</H3>
   No.
<H2>Examples</H2>
<PRE>
[eclipse]: [user].
 go:- writeln("**** Enter prolog goals and press ^D"),
      break,
      writeln("**** Execution continues...").
 user compiled 144 bytes in 0.02 seconds

yes.
[eclipse]: go.
**** Enter prolog goals and press ^D

Entering break level 1
[eclipse]: date(X).

X = "Wed Aug  9 12:21:48 1989\n"
yes.
[eclipse]: ^D

Leaving break level 1
**** Execution continues...

yes.
[eclipse]:
</PRE>
<H2>See Also</H2>
<A HREF="../../lib/toplevel/toplevel-0.html">toplevel / 0</A>, <A HREF="../../kernel/control/exit_block-1.html">exit_block / 1</A>
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